16.01.2013 Views

1EQQ8ZzGD

1EQQ8ZzGD

1EQQ8ZzGD

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

• Pooling: certain types (spies in the example) behave like<br />

other types ("pool on the same action"), making it impossible<br />

for the opposite side (the king) to figure out who is<br />

who until one type (usually the "bad" type) reveals himself.<br />

• Building reputation (for credibility, e.g.) and then burning<br />

it at an opportune time.<br />

The study of such models has become a very active area in<br />

game theory. An excellent scholarly monograph on this field<br />

is Repeated Games and Reputations: Long Run Relationships<br />

by George Mailath and Larry Sameulson (http://www.<br />

amazon.com/Repeated-Games-Reptions-Long-Run-Relationships/dp/0195300793/)<br />

— but note that this is an advanced<br />

graduate textbook with lots of math.<br />

A final big-picture remark: in these game-theoretic models,<br />

nobody is actually being tricked. Agents have accurate<br />

beliefs about what the other side is doing (that's the definition<br />

of a nash equilibrium) and are doing the best they can.<br />

Several innovative economic theorists at Stanford (Yossi<br />

Feinberg, Matt Jackson) have remarked that, for this reason,<br />

there isn't really a good model of lying in economics [1]. Real<br />

lying should involve the target being, at least potentially, an<br />

"unsuspecting victim" who really believes what he has been<br />

told. A recent paper that seems to move in this direction is by<br />

ettinger and Jehiel ["A Theory of Deception", American Economic<br />

Journal: Microeconomics 2010, 2(1), pp. 1-20, http://<br />

www.enpc.fr/ceras/jehiel/deception.pdf].<br />

[1] note, for example, that a usual justification for accurate<br />

beliefs in equilibrium is that players have been playing<br />

this kind of game a lot, and have a sense for how often the<br />

truth matches the plain-language meaning of a particular<br />

statement. Maybe that's true when five people have been<br />

playing poker together for a long time. But important lies<br />

are often told "out of equilibrium," when there is no reason<br />

to believe that players have a good "read" of the likelihood<br />

that a claim is true.<br />

226<br />

http://www.quora.com/l/boq-ben-golub

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!